THE EFFECT OF CHAIN LENGTH ON THE INTRINSIC VISCOSITY – TEMPERATURE COEFFICIENT OF LINEAR HIGH POLYMERS

Abstract

Careful measurements of the intrinsic viscosities of three fractions of polystyrene, ranging in molecular weight from 160,000 to 1,350,000, have been made over a 40 °C. range of temperature in a good solvent (toluene) and a poor one (toluene – 30% 1-butanol). These, together with similar but somewhat less accurate measurements with five fractions of GR–S, show clearly that solvent effects on the intrinsic viscosity are strongly dependent on molecular weight for linear flexible polymers, and give additional support to the concept that the differences m the intrinsic viscosity of such a polymer in good or poor solvents are due primarily to differences in the looseness or tightness of coiling of its flexible molecules in solution.